This invention relates to the cephalosporin class of antibiotics. In particular, this invention relates to cephem compounds having in the 3-position either a 1-hydroxyalkyl (or 1-hydroxyarylalkyl) group, an ester derivative thereof, or a 3-acyl group derived therefrom. The compounds of this invention are therapeutically useful antibiotic compounds or intermediates useful in the preparation of such antibiotics.
Numerous antibiotics of the cephalosporin class have been described, all possessing the same basic ring structure comprising the 4-membered .beta.-lactam ring fused to a 6-membered dihydrothiazine ring, but differing from one another structurally and biologically in many respects. Structurally, the known cephalosporin antibiotics differ in the nature of the 7-acylamino substituent and also in the nature of the substituent in the 3-position on the dihydrothiazine ring. The desacetoxycephalosporanic acids, for example, cephalexin, have a 3-methyl substituent. Numerous cephalosporins having a substituted methyl group in the 3-position have also been described. The desacetylcephalosporins have a 3-hydroxymethyl substituent. The 3-alkylthiomethyl and 3-heteroarylthiomethyl cephems have also been described. More recently, certain 3-methoxymethyl cephems were disclosed in U.S. Pat. No. 3,665,003 and 3-bromomethyl cephems were disclosed in U.S. Pat. Nos. 3,647,788, 3,668,203 and 3,637,678.
In addition to the 3-methyl or 3-substituted methyl cephalosporins, 3-formyl cephalosporins, have been prepared by chromic acid oxidation of the corresponding 3-hydroxymethyl compounds.
Another class of cephalosporins differing in the nature of the substituent at the 3-position was described in Netherlands Pat. No. 7,206,931, wherein certain 3-unsubstituted cephalosporins as well as a method for their preparation by decarbonylation of the corresponding 3-formyl compounds were disclosed.
It is an object of this invention to provide new compounds of the cephalosporin class which are useful as antibiotics or as intermediates in processes for preparing antibiotics.
It is another but more specific object of this invention to provide new structurally unique compounds of the cephalosporin class, wherein a secondary carbinol group (1-hydroxyalkyl or 1-hydroxyarylalkyl), an ester derivative thereof, or an acyl group derived therefrom is attached to the carbon atom in the 3-position of the dihydrothiazine ring.